Thrust Capacity

For ball bearing stages, the maximum force or load that can be applied in the direction of travel without damage to positioning stage components. The mounting surface (stage carriage) is pressed against the drive mechanism by means of a spring. As a result, the maximum thrust which the stage assembly can maintain is different when pressing towards the spring versus away from it. When pressing towards the spring, the force is taken up by the drive mechanism (i.e. micrometer). While pulling away, the force is being held in place by the spring. It is specified as Ta and Tb: Ta refers to the load capacity against the micrometer and Tb is the spring load capacity.